In the Eur. J. Med. Chem. 1978, 13 53-59, there are described three tetrahydroimidazo[4,5,1-jk][1,4]benzodiazepines. The compounds of the present invention differ there-from by the fact that the imidazo-moiety is substituted with an oxo or thio group and that said compounds show antiviral activity.